Die for intermolded number wheels



Feb. 7, 1967 I... H. MORIN 3,302,242

DIE FOR INTERMOLDED NUMBER WHEELS Filed. Feb. 12, 1964 2 Sheets-Sheet l INVENTOR. Aows H MoR/N AITTORNEY 5765- 7, 1957 L. H. MORIN I DIE FOR INTERMOLDED NUMBER WHEELS 2 Sheets-Sheet Filed Feb. 12, 1964 0 WM H 5 u 0 W @m R 5, N 6 Q \NN R Q.

HTTO/FNEY,

United States Patent 3,302,242 DIE FOR INTERMOLDED NUMBER WHEELS Louis H. Morin, Bronx, N.Y., assignor to Coats & Clark Inc., New York, N.Y., a corporation of Delaware Filed Feb. 12, 1964, Ser. No. 344,421 2 Claims. (Cl. 18-30) This invention relates to the production of number wheels, wherein the main body portion of the wheel, including the numbers thereon, is fashioned from one color plastic material and the sheath, at the periphery of the wheel and surrounding the numbers, is fashioned from a color contrasting to the numbers, so that the numbers will be clearly readable on the peripheral surface of the resulting wheel. More particularly, the invention deals with a number wheel, wherein the main body has, at the sides of its periphery, undercut annular grooves receiving portions of the sheath in secure anchorage of the sheath on the main body of the wheel.

Still more particular, the invention deals in a die structure for number wheels of the type and kind under consideration.

The novel features of the invention will be best understood from the following description, when taken together with the accompanying drawings, in which certain embodiments of the invention are disclosed and, in which, the separate parts are designated by suitable reference characters in each of the views and, in which:

FIG. 1 is a diagrammatic face view of one of the dies, illustrating the die slides which are employed in operative position.

FIG. 2 is a perspective diagrammatic view of a transfer I core rod, illustrating, in full lines, the gate portions at the two molding stations, with one gate portion supporting a pre-formed body at a second molding station, the molded number wheels at the two stations being out lined in dot-dash lines for simplification in the illustration.

FIG. 3 is a diagrammatic face view of the companion die, omitting the transfer core rod. FIG. 4 is an enlarged sectional detail view through part of the two dies in abutting engagement with each other and illustrating the molding of the body part of the wheel.

FIG. 5 is an enlarged broken partial section of the finished wheel, with the sheath molded thereon.

FIG. 6 is an enlarged sectional View, generally on the line 66 of FIG. 11, but illustrating the molding of the sheath on the body part of the wheel, which is illustrated in FIG. 11.

FIG. 7 is an enlarged perspective and sectional detail view, showing the formation of the numeral SEVEN and the trimmed gate at one side of the sheath of this numeral.

FIG. 8 is a bracketed diagrammatic sectional view of at least part of the two dies in spaced relationship to each other, with the core rod positioned therebetween, the die slide of the one die being shown diagrammatically in its innermost position, in other words, as though the dies were actually in engagement with each other.

FIG. 9 is a sectional view on the line 99 of FIG. 8, with part of the construction shown in elevation.

FIG. 10 is an enlarged detail view of the inner end portion of one die slide and part of two other die slides and diagrammatically illustrating in full lines the side of a finished wheel to illustrate, in part, the manner of forming the numerals on the periphery of the wheel.

FIG. 11 is an enlarged perspective view of that part of the molded body of the wheel associated with the formed numeral EIGHT and illustrating the passages in the periphery of the wheel to extend portions of the sheath to ice interior portions of the numeral EIGHT, as more clearly illustrated in FIG. 6 of the drawing; and

FIG. 12 is a perspective view of that portion of the wheel, upon which the numeral SEVEN is formed and illustrating part of the gate, which is later removed by trimming after the sheath has been formed and as illustrated in FIG. 7 of the drawing.

In illustrating one adaptation and use of my invention for producing number wheels as might be employed, for example, in connection with counting or adding machines or other apparatus of this type and kind, I employ a pair of dies 15 and '16, diagrammatically illustrated in FIGS. 1, 3, 8 and 9 and shown in somewhat more detail in FIG. 4 of the drawing. These dies have two injector stations, defined by hardened nozzle inlet keys 17, 17'; 18, 18' on the dies 15, 16, respectively. It will be understood that one color plastic material is injected through the keys 17, 17; whereas, a contrasting color plastic material is injected through the keys 18, 18 from suitable injection molding machines, well-known in the art, and, for this reason, are not shown, the discharge nozzles of the machine operating in conjuction with the keys to shear or strip the gates after injections have been completed, as with other machines of this type and kind.

In the die 15 are formed partial sprue passages 19 and 20, note FIG. 1, which register with corresponding passages ,19, 20 in the die '16, as noted in FIG. 3. The sprues 19, 19' lead to a wheel body forming cavity 21, most clearly shown, in part, in FIG. 4 of the drawing. On the die 15 is formed, at the periphery of the cavity 21, a projecting annular ring 22, forming in the resulting molded wheel body 23 an undercut side annular groove 24. It will also appear, from a consideration of FIG. 4, that the die '16 has a similar projecting ring 25 forming in the other side of the body 23 an undercut groove 26. The die 15 is also recessed to form a hub portion 27 on the body 23.

Arranged in the die 15, note FIG. 1 of the drawing, are five radially movable die slides, each of which is of the same general construction but, for purposes of distinguishing these slides one from the other, the slide 28 may be said to form the numerals EIGHT and SEVEN.

28A may be said to form the numerals SIX and FIVE.

283 may be said to form the numerals FOUR AND THREE.

280 may be said to form the numerals TWO and ONE: and

28D may be said to form the numerals ZERO and NINE.

In FIG. 10 of the drawing, the inner end portion of the slide 28A is illustrated and part only of slides 28 and 28B are illustrated and, in the bracketed area, 29, FIG. 10, would show the formation of the numeral SIX, indicated, in part, in dotted lines at 30; whereas, in the bracketed area 31 is indicated, in part, in dotted lines at 32 the numeral FIVE. These dotted line showings of numerals at 30 and 32 are on the fully molded Wheel 23 for sake of clear illustration, it being understood, however, that the fully formed wheel is not at any time positioned on the die slides 28-28D. The adjacent slides have abutting bevelled edges, as illustrated, in part, at 33 in FIG. 10 and also illustrated in FIG. 1 of the drawing.

For illustrative purposes, the slide 28A may be said to be illustrated in FIG. 4 and, in said figure, part of the cavity portions of 28A are shown at 34. It will be understood, in this connection, that all of the slides 28-28D will have similar cavity portions in molding the respective numerals on the periphery of the wheel 23-, each slide forming two of these numerals. At this time, it is pointed out that no attempt has been made to illustrate the cavity portions of the slides in FIG. 1 or FIG. 8 of the drawing.

Each slide 28-28D has, at its outer end, a recess 35 engaged by slide operating flanges 36 circumferentially spaced on a ring 37 supported upon the surface of the die 16, as clearly illustrated in FIG. 8. The flanges 36 have rounded surfaces 36' engaging the slides to move the same into operative position against the action of springs 38 mounted in each of the slides and teinsioned to normally support the slides in an extended position sufficient to clear the inner cavity portions of the slides from the molded body of the wheel 23 as and when this molded body, at the molding station defined by the key 17, 17, is stripped from both dies by a transfer core rod 39, preparatory to moving the molded body of the wheel to the second molding station defined by the keys 18, 18, as later described.

Considering FIGS. 4 and 8 of the drawing, it will be apparent that the cavity portion of the die 15 having the ring 22 thereon, as well as a cavity 27' forming the hub 27, is actually upon a cylindrical die portion 40 fixed to and keyed to the die 15 by the screw 41.

Each of the die slides 282 8D has, on its inner surface, an elongated recess 42, note FIG. 8, in which pins 43 operate in checking outward movement of each of the slides by the spring 38 and each slide has, at its inner end, laterally extending flanges, as at 44, note FIG. 9, operating in grooves in the die 15 in retaining the slides against displacement from the die. In other words, each of the slide may be said to be substantially T-shaped in cross-sectional form.

Mounted in the die 16, in axial alinement with the die cylinder 40, is a threaded rod 45, shouldered as seen at 46, and the rod 45 carries at its free end a core pin 47 which extends into the cavity 27', as clearly noted in FIG. 4 of the drawing, to form the slightly tapered bore 48 in the hub 27 of the resulting molded wheel 23.

Supported in the die 15 in alinement with the keys 18, 18'is a secondary die cylinder 49, generally similar to the cylinder 40 and fixed in a manner similar to the showing at 41, the cylinder 49 having on its surface a cavity portion 56 for reception of the wheel as molded at the first station and sufficiently enlarged to form the sheath 51 on the periphery of the wheel 23, which sheath is shown in partial detail in FIGS. 5, 6 and 7 of the drawing. It is pointed out, at this time, that the surface of the die 26 opposed to the cylinder 49 is plain and would form, when the dies are in closed position, the surface 52 of the sheath; whereas, the other opposed surface 53 of the sheath is formed in the cavity 50 of the die cylinder 49.

Considering FIG. 3 of the drawing, it would appear that the die 16 has a transfer core rod receiving recess 54 completely receiving the rod 39. In alinement with 19" and 20', the die is further recessed, as seen at 55, 55 and 55 to form, on the runners 56, 57, note FIG. 2, loop or ring portions 58 and 59, which facilitate feeding of the molded parts, for example, the first molded body portion of the wheel, indicated in dot-dash lines at 60, FIG. 2, to the second molding station, where the final molded wheel is formed, as indicated, in dot-dash lines, at 61 in said figure, 61! being positioned at the final casting station with the runner 56 in the 56 position of FIG. 2, the die 15 having a recess portion, as at 62, to partially receive 56'; whereas, the die 16 is recessed, as seen at 63, registering wit-h 55" to receive the remainder of the runner 56. In this connection, it will be understood that the gate recesses 19, 2t 62, FIG. 1, receive that part of the runners 56, 56' and 57 which extend over the outer exposed surface 39 of the transfer core rod 39, as will be apparent from a consideration of FIG. 2 of the drawing.

Part of the runner 56 leading to the molded body 60 at the first casting station is illustrated in FIG. 12 of the drawing, where it extends to a position on the body 60 at one side of the periphery thereof at the molded numeral SEVEN, as indicated at 64 in said figure. This gate 56 is later trimmed off on the surface 52 of the sheath 51,

as indicated at 65 in FIG. 7 of the drawing. This trimming takes place beyond the lower surfaces 15, 16' of the dies as and when the next successive molded body is formed at 60 in FIG. 2 and the one now shown at 60 has been moved to position registering with 61, it being apparent that 61 has then moved beyond the lower surfaces 15', 16 of the dies. As these trimming stations are wellknown in this art, no specific reference thereto is deemed to be necessary.

Now considering the formation of such numerals as ZERO, FOUR, SIX, EIGHT and NINE, having complete enclosures within their environment, it is essential to extend the material of the sheath 51 into these enclosures so that the sheath will completely envelop all edge surfaces of all of the numerals. To illustrate one of these structures, the numeral EIGHT has been selected by virtue of the fact that it has two enclosures. At this particular station, the contoured surface of the die slide 28 will have projections thereon which will form recesses, as at 66, in the molded body 60 at the first station, the recesses extending into substantially central portions of the loops of the numeral EIGHT shown at 67 in FIG. 11, as will appear from the showing of the inner terminal ends of the recesses 66 at 68 in said figure.

Now considering FIG. 6 of the drawing, it will appear that the molded sheath 51 will include a molded body 69 extending through each of the recesses 66, so that the material of the sheath will extend into the area 70, FIG. 6, filling one of the enclosed environments of the numeral EIGHT. This same structure will be provided at each of the numerals ZERO, FOUR, SIX and NINE, a single recess being necessary at each of these other stations.

After the molded body 60 has been formed at the first molding station, it will be apparent that the die 16 first moves into the open position, leaving the runner 56 and the molded body 60 supported on the core rod 39. When the flanges 36 have cleared the recesses 35 of the die slides 28-28D, the springs 38 will automatically move these slides into position, clearing the molded body 60; whereupon, the die 15 is free to move into open position. The core rod 39 is then moved to bring 56 into the 56 position, with the molded body 60 supported in alinement with the cavity 50 of the die 15 or the cylinder 49 thereof; whereupon, the dies are again moved into closed position, in which operation, the flanges 36 engage all of the slides 28-28D and move the same into operative position; whereupon, in the next cycle of operation of the molding machine, plastic material is injec ted through both stations and another molded body is formed at 60 and the final molded body is produced at 61, note FIG. 2, in other words, the initial body 60 with the sheath 51 formed thereon, the runner 57 extending to the sheath and this runner will be of a plastic material contrasting to the color of the plastic material used in forming the body 60, which has all of the numerals thereon. To illustrate possible contrasting colors, the body 60 can be formed of dark blue or black; whereas, the sheath could be formed of yellow or white. In this way, the dark numerals will be clearly visible and detectible upon the periphery of the resulting intermolded wheel 23, partially shown in detail in FIG. 4 and in its complete formation in FIG. 5.

In the next successive molding operation, a third body 60 has moved to the second molding station. The molded body 61 has moved to the trimming station and the above cycle of operation is again repeated. At this time, it is pointed out that, when 61 is moved to the trimming station, the dies 15 and 16 are partially closed around the rod 39 and runner 57 and runner 56' will be stripped from the rod 39 as this rod moves upwardly to its normally raised position. In the foregoing operation, it will be understood that runner 56 will be positioned in the 56 position in registration with 62, 63 and held in this position as the rod 39 is moved upwardly to its initial position; thus leaving the body 60 at the second molding station. In the trimming operation, both of the runners will be simultaneously trimmed from the completely molded body 61 in producing the end product, as shown, in part, in FIGS. 5 and 6 of the drawing.

For purposes of description and considering FIGS. 7 and 12 of the drawing, the finished intermolded wheel 23 may be said to employ a sheath supporting numeral rim 71, which is T-shaped in cross-sectional form and that the sheath mounted on said rim includes hook-shaped side flanges 72 engaging said rim. This results in a secure assemblage of the two molded bodies of the wheel, as well as anchorage of the sheath on the rim through the medium of the several numerals employed. The members, such as the member 69 shown in FIG. 6, which, in addition to their initial function, form key members retaining the sheath against circumferential movement on the initially molded body 60, without stress or strain upon the numerals, which further form keys having the same function. It will also be noted, in considering FIG. 12 of the drawing, that the ring 25 will be fashioned to form a fill-in portion 73 in registration with the runner 56 to provide a substantial entrance for said runner. However no attempt is made to show the means forming 73 in the other figures. It will be quite apparent that the ring 23 will be cutaway to allow the material to extend sufficiently to form 73, generally in the same manner that 69 of FIG. 6 is formed.

It will be understood that the present disclosure deals with production of one type and kind of wheel by way of illustration. However, the wheel may have any type and kind of characterizations thereon, depending upon the use to which the wheel is employed.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A die structure for producing number wheels including intermolded parts of contrasting colors, said structure comprising a pair of relatively movable dies, with a transfer core rod disposed between said dies, said dies having spaced first and second molding stations, one die including at the first station a plurality of radially movable die 6 slides having means collectively forming numerals on one part of a wheel, means on both dies forming an undercut rim on the periphery of said one part, the other die part having means operatively engaging said slide in movement 5 and support thereof in molding position, tensional means for moving the slides into open position, the first named die including at the second station a cavity forming the second part of the wheel, said core being utilized to move the first part into registering position with the cavity at the second station in separation of the dies, preparatory to forming the second part on the first part then positioned at the second station, adjacent surfaces of the dies having gates forming runners extending to both stations, and said dies having recesses receiving the runner of the first part 15 when positioned at the second station.

2. A die structure as defined in claim 1, wherein the first named die includes a die cylinder associated with said slides in forming the body portion of the first part, and the second named die having a core cooperating with said die cylinder in forming a hub centrally of the first named part.

References Cited by the Examiner UNITED STATES PATENTS 1,259,379 3/1918 13661161 235-1 1,592,568 7/1926 Orth 235-1 2,714,949 8/1955 Morin 264328 XR 2,812,548 11/1957 Quinche Et al. 1842 3,016,579 1/1962 Schlitzkus 264247 3,031,722 5/1962 Gits 264-246 3,126,429 3/1964 Safirr 264-20 3,148,413 9/1964 Latrubesse 264-255 XR ROBERT F. WHITE, Primary Examiner.

LEO SMILOW, ALEXANDER H. BRODMERKEL,

Examiners.

C. G. COVELL, T. J. CARVIS, Assistant Examiners. 

1. A DIE STRUCTURE FOR PRODUCING NUMBER WHELS INCLUDING INTERMOLDED PARTS OF CONTRASTING COLORS, SAID STRUCTURE COMPRISING A PAIR OF RELATIVELY MOVABLE DIES, WITH A TRANSFER CORE ROD DISPOSED BETWEEN SAID DIES, SAID DIES HAVING SPACED FIRST AND SECOND MOLDING STATIONS, ONE DIE INCLUDING AT THE FIRST STATION A PLURALITY OF RADIALLY MOVABLE DIE SLIDES HAVING MEANS COLLECTIVELY FORMING NUMERALS ON ONE PART OF A WHEEL, MEANS ON BOTH DIES FORMING AN UNDERCUT RIM ON THE PERIPHERY OF SAID ONE PART, THE OTHER DIE PART HAVING MEANS OPERATIVELY ENGAGING SAID SLIDE IN MOVEMENT AND SUPPORT THEREOF IN MOLDING POSITION, TENSIONAL MEANS FOR MOVING THE SLIDES INTO OPEN POSITION, THE FIRST NAMED DIE INCLUDING AT THE SECOND STATION A CAVITY FORMING THE SECOND PART OF THE WHEEL, SAID CORE BEING UTILIZED TO MOVE THE FIRST PART INTO REGISTERING POSITION WITH THE CAVITY AT THE SECOND STATION IN SEPARATION OF THE DIES, PREPARATORY TO FORMING THE SECOND PART ON THE FIRST PART THEN POSITIONED AT THE SECOND STATION, ADJACENT SURFACES OF THE DIES HAVING GATES FORMING RUNNERS EXTENDING TO BOTH STATIONS, AND SAID DIES HAVING RECESSES RECEIVING THE RUNNER OF THE FIRST PART WHEN NOSITIONED AT THE SECOND STATION. 